Oberheim Matrix 1000 EPROM chip, operating system version 1.16. The last official version released by Oberheim was 1.11; this version corrects some MIDI SysEx control issues that Oberheim overlooked, such as a really slow response to filter cutoff frequency settings. This replaces chip U804 on the main board (it is socketed, so no soldering is required). Took about 30min. – Bug fixes made by Nordcore. – MIDI NRPN parameters editing fix. – Faster processing of parameter changes that need a modulation matrix rebuild, there’s still a small lag but it’s…read more

This one was suffering from juno cancer on one voice. Uncoating the 80017 chip did partially not work (no resonance). Put a replacement chip on a socket and recalibrated all of the 6 voices. Took 2-3h For the chorus there was used a test-point on the board as input and a new pot was installed for chorus speed. Very useful! 1-2h